Turning and boring mill



June 10, 1930. E. A. MULLER 1,762,561

TURNING AND BORING MILL Filed Sept. 29, 1927 3 Sheets-Sheet l ciM .LW

[N VENTOR A TTORNEY June 10, 1930. E. A, MULLER 1,762,561

TURNING AND BORING MILL Filed Sept. 29. 1927 5 Sheets-Sheet 2 INVENTOR me ak ATTORNEY June 10, 1930. MULLER 1,762,561

TURNING AND BORING MILL Filed sept. 29, 1927 5 Sheets-Sheet 3 m M w Patented June 10, 1930 EDWARD A. MULLER, OF CINCINNATI, OHIO TURNING AND BORING MILL Application filed September 29, 1927.

My invention relates to vertical turning and boring mills and particularly to means for mounting the side-head of same.

With all other types of boring mills chattering occurs when heavy cuts are being made with tools held in the side-head. One obj ect of my invention is to eliminate this dih'iculty. To accomplish this object I form the ways for the side-head directly on the machine housing and the side-head is built around the portion of the housing on which the Ways are formed. The result is a rigid, sturdy structure in which the strains are distributed during heavy cutting. lVith such a machine tool it has been demonstrated that the size of the cut may be increased practically to the breaking pointof the cutting tool before there will be any chattering.

Another object of my invention is to construct a boring mill which permits use of its full swing. Side-heads supported wholly or partly by independent elements added for the purpose, as an auxiliary rail or a bridging across the housing, or a combination of the two, restrict the otherwise normal swing of the machine. In carrying out my invention I use no such additional members.

Side-heads of other types of boring mills have a very limited range of vertical adjustment in proportion to the swing of the machine, and therefore,it is frequently impossible to machine a relatively high piece of work on a boring mill of otherwise suitable size. Not only is it more economical to use the smallest practical size machine tool for any piece of work, but many shops have no general use for and cannot afiord to own a large boring mill. Another object of my invention is to constructa boring mill that may have its height extended disproportionately to its table diameter so as to adapt it for use in machining a relatively high piece of work.

Another object of the invention is to counter-balance the side-head so that it free of the ways and supported only by the counter-balance cable, it would hang substantially plumb.

Another object of my invention is to so form the housing and form and place the counterweight bracket as to locate the line Serial No. 222,797.

of pressure within the base of the machine and to have nothing but a substantially vertical pressure from the weight of the sidehead and counter-weight. Distortion of the housing from this weight is completely avoided.

Another object of my invention is to locate the counter-balance cable behind the rail, where it is out of the way of the machine operator in all of his working positions. I-Ieretofore the counter-balance cable has always hung in front of the rail.

Another object of my invention is to construct a highly concentrated machine using the minimum amount of floor space.

In the particular embodiment of my invention selected for illustration Figure l is a front elevation of a turning and boring mill embodying my invention, certain conventional parts not necessary to the disclosure bein omitted, and a part of the side-head and counter-balance being broken away to show the means for attaching the cable thereto,

F 1g. 2 1s a top plan view ot the same; and

Fig. 3 is a cross section on the line 33 of Fig. 1.

Referring now to the drawings, the base and sides of the frame constitute the housing H, T is the usual work table, M the main driving motor, P the tool positioning motor, R the rail, TI-I the turret head on the right end of the rail, SH the swivel head on the left end of the rail, D the driving gear box, C the clutch housing, F the feed gear boX for the swivel head, F the feed gear box for the turret head and F the feed gear box for the side-head.

The housing H has the usual ways 1, 2 and 3 on its left side, and ways 4, 5, 6 and 7 each facing in a different direction on its right side, upon which the rail R- slidcs. T he side head S is constructed with bearing surfaces which also slide on the ways l, 5, 6 and 7, and in addition, toward the rear of the housing H on the right side is formed another way 8 with which the side-head also makes sliding contact. A clamping strip 9 is secured to the housing in such position as to tend to maintain the side-head S on the Way 8. The ways are positioned to prevent backward, forward and sideward undesirable play. A gib 10 may be provided to compensate for wear on the ways 5 and 7. A similar gib 11 may be provided to compensate for wear on the ways 4 and 6. A rack 12 or other suitable means for elevating the side-head is secured to the housing I-I.

Long bearing surfaces on the side-head contacting with ways at the front of the housing facing in all directions, and an additional rearwardly positioned way, and all of said ways formed in the rigid housing; combine to effectively distribute the cutting strains, minimizing wear and eliminating chattering.

A forked counterbalance bracket 13 secured to the top of the housing I-I carries sheaves 1 1 and 15 over which the cable 16 runs. To one end of the cable 16 is secured the counterbalance weight 17 by means of an anchor 18 and to the other end to the side-head S by means of another anchor 19. The weight 17 passes through an opening 20 in the top of the housing H and is suspended within. The cable 16 is back of the rail 1%, where the machine operator cannot strike it with his knuckles when shifting levers, and where it is completely out of the way at all times.

Although a preferred form of the invention has been shown and described, it will be understood that a mechanic, working within the scope of what is claimed, may make changes, without departing from the spirit of the invention.

I claim as my invention and desire to secure by Letters Patent'of the United States:

1. In combination with 'a turning and boring mill having a housing and a side-head; ways facing in four directions formed directly on the front portion of said housing and another way toward the rear of said housing and formed directly thereon, a clamping strip maintaining said side-head in contact with said last named way, and bearing surfaces on said side-head making sliding contact with said ways. i

2. In combination with a turning and boring mill having a housing and a side-head; ways facing in four directions formed directly on the front portion of said housing and another way toward the rear of said housing and formed directly thereon, a

clamping strip maintaining said side-head in 7 contact with said last named way, bearing surfaces on said side-head making sliding contact with said ways and means for taking up lost motion between said ways and said bearing surfaces.

3. In combination with a turning and boring mill having a housing and a side-head; a counter-balance weight for said side-head, a flexible member by which said side head and flexible member are suspended secured at one of its ends to the top of saidside-head substantially at the center of weight thereof,

and at the other end to the top of the counterbalance weight substantially at the center of weight thereof, a counter-balance bracket secured to the top of the housing and so positioned that the line of pressure is within the base of said mill, and sheaves for said flexible member pivotally mounted-on said bracket in such position that said flexible member hangs vertically from said sheaves.

4;. In combination with a turning and boring mill having a housing and a side-head; a counter-balance weight for said side-head suspended within said housing, a flexible member by which said side-head and counterbalance weight are suspended secured at one of its ends to the top of said side-head substantially at the center of weight thereof, and at its other end to the top of the counter-balance weight substantially at the center of weight thereof, a counterbalance bracket secured to the top of the housing substantially horizontally equidistant from said points of attachment of said flexible member and so positioned that the line of pressure is within the base of said mill, and sheaves for said flexible member pivotally mounted on said bracket in such position that said flexible member will hang substantially vertically from said sheaves. r

5. A turning and boring mill having in combination a housing, ways formed on a front portion of said housing, a cross-rail slidably mounted on said ways, another way formed on a rearward portion of said housing, a side-head slidably mounted on the ways formed on the front and rearward portions of the housing, said side-head so formed and positioned as to have its center ofweight lie behind the cross-rail, a counter-weight for said side-head and flexible member by which said cross-head and counter-weight are suspended, said flexible member secured at one of its ends to the top of the side-head substantially at the center of weight thereof, and at its other end to said counterweight, and sheave means upon which said flexible member is supported.

In testimony whereof I have hereunto set my hand.

EDWARD A. MULLER. 

